Analytical and quality testing of cannabis is a relatively new application in natural product quality assurance. While there is certainly a growing movement towards legalized, “recreational cannabis” in the west, the medicinal use of cannabis remains at the forefront of everyone’s interest. As such, ensuring cannabis safety and quality is essential. During the last 20 years, we have seen a resurgence in both medical and mainstream interest in herbal medicines, natural product nutrition, phytopharmacology. Despite this, the near-worldwide prohibition of cannabis has all but left this plant behind, until recently. A relatively modern phenomenon is the emergence of analytical testing laboratories that offer quality and safety testing for cannabis and cannabis infused products.

Are cannabis testing laboratories or the services they offer necessary, or even of interest? Humans have been cultivating and consuming cannabis for thousands of years, seemingly without need of high-tech laboratory operations. In fact, yes, analytical and quality assurance testing for medical and commercial cannabis is necessary. The classical trajectory in modern herbal medicine commercialization is: basic research, development of therapeutic applications and then implementation of commercial quality assurance for products. Of course, commercial and medical cannabis must follow the same path that other commercialized herbal medicines are expected to follow. Guidelines for assessing quality in herbal medicines have been established by the World Health Organization (1). At a bare minimum, we should expect cannabis herbal medicines to demonstrate the same level of quality and safety.

In Oregon (USA), testing for pesticides is a requirement for cannabis and cannabis concentrates intended to be sold to the public. Currently, Oregon rules require accredited, licensed laboratories to test for about 60 individual pesticide targets and failure action limits are in the range of 0.2-2.0 PPM. In the 4 years that we have been operating as a cannabis testing laboratory, historical data demonstrates that 5-10% of cannabis inflorescence samples will fail for pesticide detections and about 25% of cannabis concentrate samples fail for pesticide detection. It’s not uncommon to see pesticide levels of 10-20 PPM in concentrates. This is because most pesticide residues are hydrophobic compounds that are extracted efficiently along with the cannabis resins. Mold testing is not technically a requirement for commercial cannabis in Oregon, but once was. While not a regulatory requirement, many producers and retailers still elect for voluntary mold total plate count tests of cannabis inflorescence in order to demonstrate quality. About 20% of cannabis samples tested for total mold plate count will have counts greater than 10,000 CFU/g--the suggested WHO limit for herbal medicines (1).

Testing cannabis for quality and safety makes a lot of sense for protecting public health and safety. This is why we see mandatory testing requirements put in place by State and local regulators. But, in fact, as medical and commercial cannabis industries mature over time, we expect to see far fewer failures for quality and safety tests. In addition to protecting public health and safety, testing medical and commercial cannabis also adds value to the products--and to producers. With proper testing and validation, labs are able to provide critical feedback related to potency in formulated cannabis products. This allows producers to develop validated formulation processes that allow them to bring consistent, labelled dosage of active compounds to market. This is critical to the maturation of the industry in general. As the industry matures, so do commercial production and Quality Assurance practices. So, it is analytical testing labs that provide the critical, independent validation data that producers need to verify the quality of their products to consumers. Lab testing doesn’t just keep contaminated, low-quality cannabis from the marketplace. It also directly validates the quality and safety of cannabis and cannabis products. It allows brands to establish themselves as true quality producers, and for a new generation of consumers to see cannabis as another valuable herbal medicine-- not just a vilified ‘recreational drug’.